Electrolytic apparatus



E. A. LE SUEUB ELECTBOLY'HC MPARATUS.

AI'PLICATIOI mm Inn. 30. I9!!- Patented Oct. 28,1919.

4 SHEETS-SHEET I E. A. LE SUEUR.

ELECTROLYTIC APPARATUS.

Patented Oct. 28, 1919.

4 SHEETS-SHEET 2 APPLICATION FILED MAR-30. 19!].

H I i E. A. LE SUEUR. ELECTROLYTIC APPARATUS,

E. A. LE SUEUR.

ELECTROLYTIC APPARATUS.

APPLICATION FILED MAR- 301 I9- Patented Oct. 28,1919.

Ital-9,715 4suszrs snzzn 59 155 1m: cm, mam PLANOURAPH ch. WASHINGTON. I! c.

UNITED STATES PATENT OFFICE.

IIERNEST ARTHUR .LE SUEUR, 0F OTTAWA, ONTARIO, CANADA, ASSIGNOR TO THE DIAMOND lldA'lCH COMPANY, OF CHICAGO, ILLINOIS, A GORPORATION 0F ILLI- NOIS- ELECTROLYTIC APPARATUS.

Specification of Letters Patent.

Patented Oct. 28, 1919.

Application filed March 30, 1917. Serial No. 158,542.

sfonon, a subject of the King of Great Britaln and Ireland, and resident of Ottawa, 1n the Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Electrolytic Apparatus, ofwvhich the following is a specification.

[y invention relates to that class of electrolytic apparatuses whereby chlorates and the like are obtained from the chloride of alkali and alkaline-earth metals, having reference more especially to the type of apparatus wherein the electrolyte is caused to flow "directly between and in contact with spaced electrodes. In this type of apparatus the anode is composed of platinum (or similar metal) on account of its chlorin resisting ropeity; and hence, in view of the rela- Ltrve y high cost of the metal, attempts have f heretof ore been made to provide a structure wherein the maximum electrolyzation with a minliinum quantity of the precious metal may be attained.

ccordingly it has heretofore been prolposed to expose both surfaces of a platinum sheet to the action of the electrolyte; but such prior constructions were commercially impracticable owing, among other things, to the relatively heavy body of platinum necessary to be employed therein in order to secure the requisite conducting capacity for current sufficient to effect commercial results, as well as stability of structure.

The principal object of my invention is the provision of an electrolytic apparatus of simple, economic and efficient character wherein both sides of extremely thin sheets of platinum, (polyxene metal alloys, and the likef) can be practically used as'tl e, ode sur ace, and wherein the maximum dis. 1 cc through which the current is required to flow is in no case more than half the longest dimension of the anode. The latter feature is one of especial practical importance since thereby a current of relatively low voltage is efficiently-an fliedto and throughout t e effective area 0 attenuated anode. Broadly considered, my invention comprehends an electrolytic apparatus having an anode composed of a thin sheet of plati-' hum (or the like) in metallic contact along its edge or edges with and supported by a heavy conductor of feeder preferably of relatively cheap metal which is adequately protected from contact with the electrolyte, and which conductor, being connected with a source of electric energy, distributes the current to and throughout the anode.

More specifically described my. invention comprises such an apparatus employing an lnclosing pair of single faced cathode elements, a pair of double-faced anode elements therebetween, and a double-faced cathode element interposed between the anode elements, said anode elements being connected and supported by a feeder which bridges the interposed cathode element.

The invention also comprises novel features of construction and combinations of parts whereby the several structural elements can be assembled or separated with facility, as desired, and also various novel features whereby other practical advantages and results are attained, all as will be hereinafter described and claimed.

In the annexed drawings Figure 1 is an end elevation of a form of electrolytic cell einbody-ifig the principle of my invention.

Fig. 2 is a transverse vertical section through the electrolyzin chamber of the cell, as on the line 22 of Fig. 1.

Fig. 3 is a side elevation of the chambered structure.

Fig. 4 is a longitudinal vertical section thereof, .as on the line 4-4 of Fig. 3. f

Fig. 5 is a perspective view of a modified structure adapted to be immersed in a vessel containing the electrolyte.

Fig. 6 is a plan of Fig. 5.

Fig. 7 is a transverse horizontal section of the same.

Fig. 8 is a perspective view showing the anode sheets and the interposed cathode element.

Fig. 9 is a vertical section through one of the feeder bars and the contiguous edges of the anode sheets, showing the insulating and protecting material for the feeder bar.

Fig. 10 is a perspective view, partly in section, of one of the feeder bars and adjuncts.

Fig. 11 illustrates the modified apparatus as in use in a {gravel arrangement of cell and liquid supply vessel hereinafter described Fig. 12 is a transverse section, similar to Fig. 7, of a modified construction embody ing a plural assembly of anode and cathode elements.

13 is a plan of another modification 110,;

wherein a single feeder bar for plural anode elements is employed.

Fig. 14 is a transverse section of the same, as on the line 14-14 of Fig. 15.

Fig. 15 is a vertical section, as on the line 15 15 of Fig. 14.

Referring to Figs. 1 to 4, inclusive, of the drawings, 15, 16 designate two spaced metallic heads, preferably of lead electroplated with copper. These heads are represented as circular in form, one being provided with a central in-projecting stud 17 which termin-ates short of the other head 15. This stud supports, midway between the two heads, a disk-like body 18, of similar metal, which, in conjunction with the heads, constitutes the cathode surface of the cell. The sides of the disk are illustrated as corrugated in order to present as large a surface as possible to the electrolyte. Preferably the stud is screwthreaded and the disk is centrally perforated and tapped for ready mounting and ad ustment on the stud.

The heads constitute the side walls of an electrolyzing chamber, and they are spaced apart by a series of annular members which provide, among other things, the circumferential rim or wall of the structure, as will be hereinafter described. One of the heads is provided at its lower portion with an inlet into which leads a supply pipe 19 for a solution to betreated, and the other head is provided with an upper chambered portion 20 terminating in an outlet from which extends a discharge pipe 21 for the solution after it has been subjected to the electrolytic process. In the present instance, I have represented a suitable reservoir 22 to which the said inlet and discharge pipes are connected, whereby the solution may be circulated through the electrolyzing chamber until the requisite electrolyzati'on of the solution has been attained; such reservoir thus constituting a component part of the cell. The top of the reservoir is provided with a suitable vent 28 for the liberated gases. (See Fig. 1.)

The reservoir is illustrated as provided with an internal partition 22, the top of which terminates somewhat below the level a: of the liquid contents of the reservoir. This partition divides the interior of the reservoir into two chambers or compartments whereof the outer or right hand charm her (a) is of larger capacity than the inner one (7;). Since these chambers are in open communication with each other at the top, the liquid in the outer chamber is contributory to the inner chamber and permits the prolonged operation of the apparatus without changing the solution. Owing to the fact that the solution under treatment becomes constantly of a lighter and lighter specific gravity there is a constant automatic circulation of the portion of the liquid in the outer chamber (a), such liquid thus being completely tributary to the electrolytic action. This is a desirable feature in the practical operation of an apparatus wherein many cells are arranged in series, as the construction described permits the outer chamber to be emptied and replenishcd without the otherwise necessity of opening the circuit on the cells, which would, of course, result in the temporary stoppage of the entire series.

The heads 15, 16 when composed of lead, are preferably re-inforced by external rings 24 of cast iron, having on their inner faces appropriate grooves 25 into which the mob ten lead is run and therein interlocked; the contraction of the metal, on cooling. causing the associated parts to be drawn together and held with great force.

The annular rim members above referred to comprise a main conducting ring :26. pref-- erably of lead, which is protected on its under surface from attack by the cell action by an insulating ring 27 of hard rubber, porcelain or the like; two rings 28 of suitable insulating material, such as hard rubber, embracing and supporting the conducting ring and also contributing to the protection thereof; and gaskets 29, of suitable material, such as rubber-filled cloth, interposed between the respective rings 28 and the adjacent heads of the cell so as to in sure an effective joint between the heads and the insulating rings, especially when such heads are unmachined castings. These heads are preferably provided on their inner faces with annular flanges 30 which support the proximate insulating rings.

The anodic terminal 31 is conveniently embedded in a lug 32 projecting from the conductin ring 26, and the cathodic terminal 33 is secured to the reinforcing ring of the head 15 by means of a binding screw 34. l

35 designates two thin sheets of platinum (or the like,) arranged in the respective spaces between and in parallel relation to the central disk 18 and the side Walls of the cell. These sheets, which constitute the anode surface, are illustrated as of circular form with a central orifice 36 therein, and also with openings 37, 38 at the lower and upper portions respectively of the sheets. The circumferential edges of the sheets are interposed and tightly clamped between the sides of the conducting ring and the proximate insulating rings respectively, the edges of the central openings of the sheets encircling shouldered bushings 39, of insulating material, which are conveniently applied to the stud contiguous to the respective sides of the central anode member. Insulating washers 40, carried by the bushings, are interposed between the central member 18 and the respective Sheets, which "6-5 with hot water) washers, together with the bushings, insure the accurate tensionin and positioning of the thin sheets '35 in re ation to the conducting ring and the adjacent subdivisions of the cathode surface, and also thecentering of the member 18 and its jamming on the threaded portion of the stud. The openings 37, 38 in the sheets permit the free flow of the solution and products of decomposition throughout the cell. Instead of forming the openings 87, 38 in the upper and loWer portions of the anode sheets appropriate passages may be provided by reducing the sheets at top and bottom as indicated by the dot-and-dash lines in Fig. 2.

The various parts arranged in cooperative relation to each other as above described are firmly locked together in order to secure good electrical contact and to effect a water-tight assembly, and also to insure eflicient distribution of the current; it being noted, in this connection, that the ring or feeder (which in this instance is of base metal) supplies current to a pair of doublefaced anode elements while bridging a double-faced cathode element, and that said anode and cathode elements are inclosed by and between a pair of single-faced cathode elements.

The form of locking means herein shown is of such character that the parts can be readily released and disassembled for inspection, cleaning, renewal or repair, as desired; such means comprising a crosspiece 41, cast on one of the reinforcing rings, provided with a depression for the reception of a clamp-screw 42 which is mounted in one limb of a clamp-yoke 44 snu ly embracin the structure. By tightenlng this screw are two heads and the interposed parts are firmly forced and locked together, and, on the other hand, by loosening the screw the yoke may be released and removed and the several parts of the structure be readily disassembled, as above mentioned.

In order to establish and maintain a thorough gas-tight joint around the conductin ring and thus protect the metal thereo from injurious attack by the nascent chlorin (which is a most powerful reagent,) and at the same time to insure intimate electrical contact between the said ring and the contiguous edges of the platinum sheets, I construct the protective insulating ring 27 a trifle wider than the encircling conducting ring, and form such insulating ring and the lateral rings 28, or the latter only, of a plastic or potentiall plastic material, such, for example, as ard rubber. Then when the parts of the apparatus have been assembled and locked together as above described, (and preparatory to the perfonnance of the electrolytic rocess) the apparatus is bodily heated convemen'tly amanner to render the insulatingmaterial plastic and insure thereby the important sealing and contact effects above mentioned.

I wish toremphasize the importance of the sealing feature just described, since it is essential that the electrolyte shall not come into contact with the base metal feeder, as otherwise the latter will be rapidly destroyed. The heat developed in the platinum by the passage therethrough of the current where the platinum is inclosed between the insulating surfaces, is dissipated in two ways, viz.: conduction through the platinum itself outwardl and inwardly (to the base metal feeder an to the electrolyte) a maximum distance of approximately three-thirty seconds of an inch, each way, and conduction through the hard rubber to the electrolyte and to the ring 26.

It is to be noted that the level of the liquid contents of the reservoir 22 (which as above stated constitutes a part of the cell) is maintained above the base metal ring or feeder, as indicated in Fig. 1. All the anode and cathode surfaces are thus located below the surface of the liquid in the reservoir, and hence there is no existent air gap between the liquid and the insulation of the base metal feeder. Consequently the platinum, with the exception of the small portion thereof incased by the insulation, is fully immersed in the electrolyte and, therefore, the maximum anodic action on the liquid is attained. This is an important feature of my invention.

By the construction above described extremely thin or attenuated sheets of platinum are effectually supported, circumferentially and centrally, in operative spaced relation to the subdivisions of the cathode surface, whereby both faces of each sheet are efliciently presented to the electrolyte in a manner to insure the maximum electrolytic effect with a minimum quantity of the precious metal. Furthermore, by virtue of the circumferential mounting of the conducting ring on the platinum sheets the maximum distance through which the current is required to flow in such sheets is in no case more than half the longest dimension of the anode, thereby insurlng the eflicient application of a current of low voltage to and throughout the effective area of the anode.

In the commercial electrolytic production of chlorates great heat is generated in the apparatus, the excess heat, unless adequately dealt with, rapidly destroying the apparatus. This is a vital factor and hence various mechanical heat con-trolling devices have been proposed and adopted with eXist-' ing types of apparatus. By virtue of'the construction of my apparatus, however, I am enabled to maintam the temperature at an eflicient degree by the simple expedient of immersing the apparatus bodily in water which is maintained at a predetermined temperature by circulation or otherwise. I have discovered that the apparent objection to this step, viz.: that the current will flow through the water fromthe external portions of the conducting ring to those of the side heads, does not substantially exist in that the water constitutes a practical insulator for the voltage used, even when the water is charged with the impurities usually present in ordinary water supplies. The described mode of reducing the temperature rendered possible by the novel construction of my apparatus has furthermore the distinct practical advantage of keepin the peripheral cell parts cooler than if t e contents of the cell were maintained at a stated temperature by means heretofore employed for that purposethereby increasing the duration of the apparatus.

While in the foregoing described construction a single central cathode member flanked by two anode members is employed, it is to be understood that in pursuance of my invention two or more of such cathode members with an increased number of relatively spaced anode members may be used.

In Figs. 5 to 15, inclusive, of the drawings I have illustrated modified forms of embodiment of my invention.

In the construction shown in Figs. 5 to 11, inclusive, the two spaced members, constituting the cathode surface, comprise rectangular cast-iron plates 15 having on their inner faces oppositely-disposed vertical end flanges between which heavy feeder bars 26 (preferably of base metal) for the anode surfaces are clamped. The cathodic terminal 33 is electrically connected to one of the plates, said terminal having a suitable protective covering 33 of hardrubber. Each of the bars is entirely incased and rotected by a casing 27' preferably of har rubber, excepting at the lateral portions where the casing is slotted to enable electrical contact to be established between the bar and the marginal portions of thin sheets 35 of platinum (or the like) constituting the anode surface. (See Figs. 9' and 10.) Protecting stri s 28 of insulating material, preferably ha rubber, are interposed between the sides of the feeder bar and the proximate end flanges of the side plates, such strips effectually covering and protecting the contact margins of the anode sheets and also the adjacent sides of the feeder bar. Each of the feeder bars is provided with an anodic terminal 31 having a protective covering 31, the latter being screwed into a tapped orifice in the top of the casing 27 as seen in Fig. 9.

The casing 27 for each of the bars 26 is analogous to the hard rubber ring 27 in the first described construction, and, similarly to said ring with respect to the feeder rin 26, the casing 27 is made somewhat wi er than its associated feeder bar 26', and, prior to being put into electrical service, the apparatus is eated and the clam .ing device thereof is pulled up in order e ectually to seal the feeder bars within the respective enveloping casings therefor constituted by the associated slotted elements 27 and the stri s 28.

e two plates 15' and the interposed elements, are adequately clamped together by means of a central bolt 44 which passes through an opening in a medially-disposed division plate 18'. This plate ispreferably of cast iron, and, similarly to the corresponding plate in the first described construction, 1t constitutes a art of the oathode surface. It is adjustably held in place bylclamp nuts or bushings 39 on the screw b0 t.

The anode sheets 35 are arranged in the respective spaces between and in parallel relatlon to the central member and the side plates, such sheets being centrally perforated and supported upon and by insulating members 40 on the clamp nuts or bushings on the bolt 39, as best seen in Figs. 6 and 7.

The modified form of apparatus just described. is designed to be sup orted within a suitable vessel containing t e electrolyte, the apparatus being preferabl entirely immersed. The correlated catho ic and anodio surfaces are thus presented to the liquid in a manner to insure the maximum cathodic and anodic operations. Preferabl the outer cathode plates 15' are foraminate as shown in order to permit electrolytic reducin action all over the backs of the said pfittes, whereby they are rotected from chemical attack by the hypoc lorous acid and the like contained in the electrolyte.

In Fig. 11 I have illustrated the apparatus just described as supported within a vessel A which is arranged within and in open communication with a larger vessel B containing the electrolyte. Thus the liquid in the outer vessel is tributary to the electrolytic action of the inner cell and permits the prolonged operation of the apparatus without changing the solution, as previously mentioned with reference to the first described construction.

In the modified construction a lurality of internal cathode members witl i an increased number of relatively spaced anode members may be employed, as clearly illustrated in Fig. 12, in which view the cathode terminal is shown, for convenience, as swung through 90 from its actual position.

In the construction shown in Fi s. 13 to 15, inclusive, the feeder for the ano es comprises a centrally located feeder body 26* (preferably of base metal) interposed between the spaced side plates 15, said body being incased and protected by a slotted insulating casing 27 and lateral insulating strips 28 similarl to the modified constructions previously escribed. An anodic terminal 31, with its protective covering, is a plied to one end of the bar. The two si e plates, with the interposed feeder body, are clamped together by spaced screw-bolts 44*, which pass through openings in the respective sections of a two-part plate 18 which is medially located between the side plates. The inner or adjacent, edges of the plate sections 18"bear closely against the opposite sides of the slotted insulatin casing 27 enveloping the feeder bar, w ereby liability of the separation of the casing material from the feeder by the influence of the heat on such material during the operation of the cell, is obviated.

Each of the anode sheets is illustrated as comprising two sections, 35 arranged on opposite sides of the feeder so as to he in t e respective spaces between the central cathode sections and the adjacent side member; the inner vertical edge of each anode section being in intimate electric connection with the feeder and being adequately covered and bound thereto by the protective insulating material 27, 28 similarly to the constructions previously described.

The side plates are provided with central vertically disposed ribs 45 which are clamped against the opposing insulatin strips 28 on the feeder bar by means 0' spaced screw bolts 44* whereof each passes through the two side plates and is provided with a binding nut.

The anode sheets 35 are perforated for the free passage of the bolts 44*, and the latter are furnished with suitably-spaced and insulated washers 46 and nuts 47 for the support of the sections 35 contiguous thereto. hf

One of the side plates is fllilP-ped adjacent the feeder 26 with inwar y extending screws 48 against the heads of which bear the adjacent faces of the respective cathode sections 18*. This plate is also provided at or near each end with two spaced apart setscrews 49 against which the face ofeach section also bears; there thus being three spaced lateral supports for the section. The inner screws, 48, in view of their location adjacent the feeder bar, pass through orifices in the proximate anode sections and are therefore adequately insulated from the latter by insulating bushings 50. The screws 49 are disposed outwardly beyond the edges of the anode sections, and so require no 1nsulation. The two sets of supporting screws are appropriately adjusted in order to insure the correct positioning of the respective cathode sections, and the appropriate nuts 47 on the bolts 44* are manipulated so as to force and hold the sections tightly against the screw. supports.

are conveniently faced oif in the same oper ation and at thesame level a the faces of the median ribs 45. Thereafter, in setting up the cell, ca'lipering is resorted to between opposite teats so as, in screwing up the nuts on the bolts, to position and tighten both sides of the cell structure and the intervening anode and cathode sections in parallelism.

Other modifications within the principle of my invention and the scope of the appended claims will suggest themselves to those skilled in the art to which the invention appertains.

I claim- 1. In an electrolytic apparatus, a metallic anode sheet, a relatively heavy feeder and support therefor in electrical contact with and throughout the length of a narrow margmal portlon of the sheet, said marginal portion and the adjacent surface of the feeder being coated with insulating material, and lateral members embracing the feeder and anode sheet and clamping together their contacting portions.

2. In an electrolytic apparatus, a metallic anode sheet, a relatively heavy feeder and support therefor in electrical contact with and throughout the length of a narrow marginal portion of the sheet, said marginal portion and the adjacent surface of the feeder being coated with insulatin material, lateral members embracing t e feeder and anode sheet and clamping together their contacting portions, and means remote from said feeder contributing to the support of said sheet.

3. In an electrolytic apparatus, a plurality of metallic anode sheets arranged in spaced relation to each other, a relatively 'heavy feeder and support therefor interode member.

5. An electrolytic apparatus comprising spaced side walls having a double-faced cathode member therebetween, double-faced anode members flanking said cathode member in spaced relation thereto, an anode feeder and support bridging the said cathode member, and means insulating said feeder from the side walls.

6. An electrolytic apparatus comprising spaced side walls having a double-faced cathode member therebetween, double-faced anode members in spaced relation thereto, an anode feeder and support bridging the said cathode member, said anode members having their edges overlapping the respective sides of the feeder and in electrical contact therewith, and insulating material between the feeder and the side walls, said material overlapping the marginal portions of the cathode members.

7. An electrolytic apparatus comprising spaced side walls constltuting the cathode surface, a thin metallic sheet constitutlng the anode surface, arranged in the space between said walls, a feeder of relatively cheap metal affording a support for and being in electrical contact with and throughout the length of a narrow marginal portion of said sheet, and means for insulating said feeder from the walls and for protecting it from attack by the products of the electrolytic action.

8. In an electrolytic a paratus, an anode comprising a thin meta l1c sheet, a heavy feeder of relatively cheap metal supporting said sheet along its outer edge and being in electrical contact therewith, means pro tecting said feeder from attack by the products of the electrolytic action, and means supporting said sheet at or about the center thereof.

9. An electrolytic apparatus comprising s aced side walls, an internal member spaced tlierebetween, said Walls and member constituting the cathode surface, thin metallic sheets constituting the anode surface, arranged in the spaces between the said memher and the respective side walls, a feeder of relatively cheap metal supporting said sheets and being in electrical contact therewith, and means for insulating said feeder from the walls and for protectin it from attack by the products of the e ectrolytic action.

10. In an electrolytic apparatus, an anode consisting of a thin metallic sheet, a heavy annular feeder of relatively cheap metal circumferentially bounding and supporting said sheet and being in electrical contact therewith, and means protecting said feeder from attack by the products of the electrolytic action.

11. In an electrolytic apparatus, an anode comprising a thin metalhc sheet, a heavy annular feeder of relatively cheap metal bounding and supporting the outer edge of said sheet and being in electrical contact therewith, means protecting said feeder from attack by the products of the electrolytic action, and means supporting said sheet at or about the center thereof.

12. In an electrolytic apparatus, an anode comprising a thin metallic sheet, a heavy annular feeder of relatively cheap metal circumferentially bounding and supporting said sheet and being in electrical contact therewith, means protecting said feeder from attack by the products of the electrolytic action, and a central support for said sheet.

13. An electrolytic apparatus comprising spaced side walls constltuting the cathode surface, a thin metallic sheet, constituting the anode surface, arranged in the space between the said Walls, a feeder of relatively cheap metal boundin and supporting said sheet and being in efectrical contact therewith, and means for insulating said feeder from the Walls and for protecting it from attack by the products of the electrolytic action.

14:. An electrolytic apparatus comprising spaced side walls having a double-faced cathode member therebetween, a pair of doublefaced anode members flanking said cathode member in spaced relation thereto, a basemetal feeder and support for the anode members, said feeder bridging the cathode member, and means insulating said feeder from the walls and for protecting it from attack by the products of the electrolytic action.

15. An electrolytic apparatus having a base metal feeder, an insulating and protective covering for said feeder, and an anode member having a marginal portion in close electrical connection with said feeder, said covering overlapping such marginal portion.

16. An electrolytic apparatus having a base metal feeder, anode sheets having their edges overlapping and in electrical contact with the res ective sides of the feeder, a hard rubber insulating and protective substance on said feeder comprising a portion covering the inner surface of the feeder between the anode sheets and portions covering the sides of the feeder and overlapping the edges of the anode sheets on the feeder.

17. An electrolytic apparatus comprising spaced side 'walls and an internal member spaced therebetween, said walls and member constituting the cathode surface, a base metal feeder interposed between said walls, double-faced anode sheets fiankin said internal member in spaced relation t ereto and to the side walls and having edge portions overlappin and in electrical contact with the respective sides of the feeder, an insulat mg and protective substance on the inner and lateral surfaces of the feeder, said substance overlapping the edges of the anode sheets laterally of the feeder, and means for clamping together the said side walls and the interposed elements.

18. An electrolytic apparatus having single-faced cathode elements constituting inclosing walls, a pair of doublefaced attenuated anode elements therebetween, a doublefaced cathode element interposed between the anode elements, a base metal feeder supporting said anode elements and bridging the interposed cathode element, plastic or potentially plastic insulating material for said feeder, and clamping means for said walls.

19. An electrolytic apparatus having an anode feeder, anode members having their marginal portions in contact with the feeder, lateral embracing elements for said feeder, plastic or potentially plastic insulating material interposed between said feeder and the adjacent elements and overlapping the marginal portions of the anode members, and clamping means for said elements.

20. An electrolytic apparatus comprising spaced side walls having an internal member spaced therebetween, which member, together with the side walls, constitutes the cathode surface, thin metallic sheets constituting the anode surface, arranged in spaces between the said member and the respective side walls, an annular feeder of relatively cheap metal bounding and supporting said sheets and being in electrical contact therewith, and means for insulating said feeder from the walls and for protecting it from attack by the products of the electrolytic action.

21. An electrolytic apparatus comprising spaced side walls one of which is provided with an inwardly-projecting stud, an internal member supported upon said stud in Copies of this patent may be obtained for spaced relation to the side walls, which member, together with the side walls and stud, constitutes the cathode surface, thin metallic, sheets constituting the anode surface, arranged in the spaces between the said member and the respective side walls, insulating means supporting the said sheets on the stud, an annular feeder of relatively cheap metal bounding and supporting said sheets and being in electrical contact "therewith, and means for insulating said feeder from the side walls and for protecting it from attack by the products of the electrolytic action.

22. An electrolytic apparatus comprising two circular heads one of which is provided with an inwardly projecting central stud, an internal member supported upon said stud in spaced relation 'to the inner sides of the heads, which member, together with the heads, constitutes the cathode surface, a circumferential feeder, lateral insulating rings between said feeder and the respective heads, a protective insulating substance on the inner surface of the feeder, circular metallic sheets constituting the anode surface arranged in the spaces between said member and the respective heads, and having their circumferential edges clamped in electric contact with the said feeder by the proximate lateral insulatin rings, insulating means centrally supporting the sheets on the said stud, and means for clamping in assembled position the said heads and the interposed ring elements.

Si ned at the city and county of Oswego, and tate of New York, this 26 day of March, A. D. 1917.

ERNEST ARTHUR LE SUEUR.

Washington, D. 0. 

